Full Color Pixel with Vertical Stack of Individual Red, Green, and Blue Transparent Organic Light-Emitting Devices Based on Dye-Dispersed Poly(N-vinylcarbazole)

A organic light-emitting device (OLED) with the transparent electrodes has the specific feature of being transparent over the visible spectral range when light is not emitted. We can fabricate such a transparent device that emits red, green or blue light by choosing a light-emissive material for each color. Furthermore, This transparency enables us to fabricate a full color display by stacking these transparent red, green, and blue (RGB) devices. In this display, RGB lights are emitted from one pixel, each with controlled individual emissions of light. In our experimental device, white light with chromaticity coordinates (x,y) of (0.31,0.33) was obtained, when all the devices of a pixel were turned on. The average color rendering index (Ra) was 87.8.